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# How to determine the direction on tension watch

1. ^ mass doesn't matter. We consider only the particles at M1. Hence that dotted line separating the free body force diagram of the particles.

Hope no one got confused but it had to be pointed out as wrong.
2. (Original post by StUdEnTIGCSE)
Here
Oh, now I understand what you were talking about. I was focusing on the claim that "we don't consider the string".

But yes, tension does go outwards :
3. My teacher always taught it as the tension always acts away from the particles/objects the string is attached to. For example, if a string is pulling an object along, the tension would be facing away from the object. If there is a string joining two objects that are moving, then there are two tensions, one pointing away from the first object and one pointing away from the second.
4. Ignore me. I was being wound up by the claim that we don't consider the string
5. (Original post by StUdEnTIGCSE)
Here
ill see what solution bank says

solution bank confirms it, thank you for your input
6. I don't much like some of the commentary in this thread.

When a string is under tension, just draw two arrows pointing towards the centre of the string like this --> <--

Label both arrows T as they have the same magnitude.
7. (Original post by Mr M)
I don't much like some of the commentary in this thread.

When a string is under tension, just draw two arrows pointing towards the centre of the string like this --> <--

Label both arrows T as they have the same magnitude.
ok but what happens when you resolve a certain way say you have an object Q which is going this way ->
you resolve -> and t will be negative, similarly for P you resolve -> so T will be positive for P?

Is this always the case, what if its on an inclined plane, do you take tension to be negative or positive ty
8. (Original post by Robbie242)
ok but what happens when you resolve a certain way say you have an object Q which is going this way ->
you resolve -> and t will be negative, similarly for P you resolve -> so T will be positive for P?

Is this always the case, what if its on an inclined plane, do you take tension to be negative or positive ty
You should be able to grasp what's happening when you are given a situation. The standard car dragging a trailer up a hill is probably the best example. When the system is accelerating the tension will pull back on the car and pull forward on the trailer, because it needs to pull the trailer along. However, when the system is decelerating the tension in the towbar becomes a thrust which pushes forward on the car and pushes the trailer backwards.
9. (Original post by Robbie242)
ok but what happens when you resolve a certain way say you have an object Q which is going this way ->
you resolve -> and t will be negative, similarly for P you resolve -> so T will be positive for P?

Is this always the case, what if its on an inclined plane, do you take tension to be negative or positive ty
I think you are making this much harder than it needs to be. If you private message me with an email address I will send you a couple of powerpoints.
10. physics seems hard,wish i had the brains to do it-biology is as far as my science skillz go-.-

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